Everything's in technicolor for Hilary Duff right now.

Hours after announcing she's pregnant with her fourth baby, her third with husband Matthew Koma, the How I Met Your Father alum proudly showed off her baby bump on Instagram. 

The 36-year-old, clad in a white tank top, captioned the Dec. 12 selfie, "Been trying to hide this thing for a minute."

Hilary first shared her pregnancy news earlier in the day by posting her family's sweet holiday card, which showed the Lizzie McGuire alum embracing her growing bump.

"So much for silent nights," the card read, while the Disney star captioned the announcement, "Surprise Surprise!"

And Hilary—who is already mom to kids Luca, 11, who she co-parents with ex-husband Mike Comrie, as well as her and Matthew's daughters Banks, 5, and Mae, 2—has always been vocal about how pregnancy and motherhood are labors of love. 

"The boobs are big the belly is big the body is big. Man.. pregnancy is hard," she captioned a July 2018 Instagram post. "Giving love to all mamas who make it look effortless... this journey is hard as hell and also incredibly special."

"Lovely to have a little life inside and to day dream of all the new adventures to come buuuut almost impossible to get my own shoes on..sick of getting up 9 times a night to pee and looking at this weird body in the mirror that is not my own at the moment," she continued. "Women are so bad ass, this was just a note to remind myself and remind others how's strong and beautiful you are! WE GOT THIS."

And as for motherhood, the Younger actress emphasized to moms that "everything takes time."

"It took time to build the baby," she said in a 2019 episode of The Motherly Podcast. "And that's a very obvious thing to say, but really, I try to remind myself that all of this stuff is a blip in time."

Keep reading for more of Hilary's iconic quotes about motherhood.

The actress announced her third pregnancy, which marks her and Matthew's second child together. "We are growing!!! Mostly me," she cheekily shared on Oct. 24.

"My guys is getting an expander and starting 3rd grade!!!!!! SOS it's going too fast! Slow down the tape," she wrote on Instagram.

"Just like you, I'm juggling a million things a day: working from home, changing diapers, and trying to navigate virtual learning. Sometimes my head is spinning and I truly have NO idea what's going on," she expressed. "And you know what? That's totally OK! We need to normalize not having it all together!!!"

"Ok a few thoughts ... 100% real talk this is the first day I had two kids on my own on a school morning. Breastfeeding and making breakfast, getting 2 kids and myself dressed and packed and out the door while tripping over 4 dogs and feeding the damn fish was not easy. But I did it. And I'm proud of myself!" Duff wrote on this snap in January. "Im proud of every mom out there who MAKES IT FREAKIN HAPPEN. All day! Everyday! You are the shit! Bad ass, super goddess , world taker oner and you deserved to be praised❤️ ps laying outfits out for me baby and Luca was essential lol I even got 5 minutes to do some make up ..... then turned around to see Luca had used my lipstick as warrior paint on his face."

"Calling all parents of colic babies.....this ends right? Can you ever set them down with out them screaming OR waking up?" Duff asked her fellow mom followers in January after dealing with a colic baby. "We have read everything the internet has to offer... nothing besides nursing basically every hour or less helps! We have done all the obvious things ..please leave magic tricks in comments. Oh and happy new year lol #thankGforfilters #babyforsale!!! #anytakers."

"We two months in sister. Been a lot of sleepless nights and you sure do scream a lot. But you are worth every moment my little strugglebunny," the Texas native shared about life with her new baby girl in December.

"Having kids changes everything. Life's not really about you anymore," the Younger star told MyDomaine in December. "Having kids has taught me unbelievable patience and brought immense joy to my life." The one thing she wished she knew before having kids however is how much sleep she'd actually be getting. "I would have stocked up on sleep like a bear hibernating in the winter," she joked.

"Don't get too get fancy very often these days. So I took a selfie to remember my old self ☺️... however the real thing to remember is that this tiny baby and spit up and sweat pants and not leaving the house is temporary and will actually be a phase that is gone too quickly❤️" Duff admitted on social media in December. 

"I don't always balance it all, I do the best that I can, and some months are crazier than others," Duff told E! News in an exclusive interview in April. "I'm a mother first, so he's always my number one priority. And then my decision-making process is like, 'Hey can I make this work? Is he going to get enough of what he needs from me?'"

"I think that pregnancy really prepares you and gets you ready for motherhood, you never know exactly quite what to expect," the blonde beauty told Parade after having kids. "On the positive side of things, it's amazing. I really felt like my life literally grew and you don't even know it's possible. It's taught me a lot of patience and to slow down and don't let the days pass you by."

"You're always worrying," Duff told Today about parenthood. "Everyone wants their kids' lives to go perfectly, which is obviously not possible all the time. But it's so fun. I'm so lucky."

While pregnant with her daughter Banks in July 2018, the actress revealed the truths about pregnancy on Instagram with this bikini bump snap. "The boobs are big the belly is big the body is big. Man.. pregnancy is hard. Giving love to all mamas who make it look effortless... this journey is hard as hell and also incredibly special," she shared. "Lovely to have a little life inside and to day dream of all the new adventures to come buuuut almost impossible to get my own shoes on..sick of getting up 9 times a night to pee and looking at this weird body in the mirror that is not my own at the moment. Women are so bad ass, this was just a note to remind myself and remind others how's strong and beautiful you are! WE GOT THIS!"

"Best thing that ever ever happened to me. I got the privilege of becoming a mother... and everyday I am grateful for his. #happymothersday to every mom out there that feels the same as I do," Duff wrote in 2017 for Mother's Day. "A mothers job is never done. But what a rewarding job it is❤️❤️."

"I think it has to happen slowly. I can only speak for my family and I know how hard it is to introduce nontraditional ideas, but you have to do what feels right," Duff told Parents.com about trying to navigate co-parenting and a new family. "By the way, just because you are a parent doesn't mean that your needs aren't important. That was a big thing for me to get over through my whole experience of trying to stay a team and a family outside of some normalcy shifting. I feel really lucky that Luca has the dad that he does, we have the relationship that we do, and I didn't make any big decisions quickly like moving forward with my life or introducing another child or person. I took my time with everything and I think that was the best for me and for Luca. And watching what you say is key, key, key."

"This beautiful poem was given to me from the wonderful peter Herman who plays Charles on @youngertv I have to spend many days sometimes weeks away from luca when shooting and he gave me this poem when I was desperate to see and hold my boy," Duff shared along with a sweet poem in July 2017 admitting she missed her son. "Tears started falling down my face at the last four lines and still do when I read it. Motherhood is the greatest gift I have ever received. Everyday a new adventure or hurdle. My heart has grown bigger than I can explain. I think every mother or parent will find this poem as moving as I do ❤️enjoy."

"I started to feel less guilt about taking time for myself, or you know, maybe not putting Luca to bed one night and going out with my girlfriends and having a fun dinner," Duff shared with E! News before welcoming baby number two. "That stuff rejuvenates you, and I matter too."

When asked how important it is for Duff and her partner Matthew Koma to parent 50/50, the singer revealed that it is so not the case that mom and dad's responsibilities are split in half. "I don't believe in that; any mom would know that it's not 50/50. We have a way bigger responsibility always and forever," Duff told Parents.com. "I think it is important that they help in a different way that doesn't always pertain to the baby and the kid. I am a very proactive person and [Matt] is extremely helpful and I know he is going to be a natural but, in the beginning, the mom has most of the responsibility, so they have to pick up the slack in other areas."

"I always feel torn or guilty about something. I'm not working right now, and at first I stressed about that, like, 'Oh, I shouldn't stay still this long.' And that's ridiculous. I have a child; it's totally fine to not be slammed all the time," she told RedBook in 2017. "It feels really good to not be on someone else's schedule — besides Luca's. I'm basically his chauffeur!"

"Some of my friends tell me, 'God, it must be so nice, you get a break from your kid because you share him.' I'm divorced, and it sucks," Duff told Redbook in 2017 about the truth about co-parenting with her ex Mike Comrie. "Well, it did suck for a while; now it's just normal. But it's true, I do get a break. I had Luca by myself for a few weeks, no help, when Mike was on the road, and when he got home I was like, 'He's yours! Bye!'"

"Women are so amazing," the 31-year-old star told Shape when talking about women and their bodies post baby. "When I look at my body and see stretch marks from being pregnant, or my boobs aren't where they used to be, I look at Luca and think, 'I can't imagine my life without you, so if I have a few of these battle wounds from having you, I don't really care.'"

After posting this sweet snap from Disneyland in 2016, Duff took to Instagram to clap back at haters judging her kiss with her son Luca. "For anyone commenting that a kiss on the lips with my four year old is ‘inappropriate' go ahead and click a quick unfollow with your warped minds and judgement," she wrote.

"Even before you have your baby you can start feeling the judgment. Becoming a mother that whole process is so special and so magical really, but it's also very isolating," Duff told Entertainment Tonight in 2015 about all of the judgement a parent gets from others.

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