Alyssa Milano has been no stranger to posting photos of herself breastfeeding her children - So, it wasn't a surprise that the 42-year-old proud mama-of-two choose to celebrate her daughter Elizabella's first birthday Friday by posting a throwback photo of herself nursing her little one.

"Happy Birthday, my beautiful Elizabella," she captioned the magical moment in honor of her daughter's special day. "You've taught me that my heart has no end. You were the missing piece to my soul. Thank you for choosing me."

However, not everyone was happy with Milano full-exposure photo. Users felt the photo should have remained a private moment between mother and child while others said they were tired of seeing photos of the actress breastfeeding her children.

The former "Charmed" actress told "Entertainment Tonight" that she found the online backlash over her photo hypocritical since other social media users often post photos with less clothing and more revealing than her breastfeeding photo - using Miley Cyrus exposing her nipples on camera countless times at the MTV Video Music Awards without major backlash.

"I don't care. I'm going to keep breastfeeding, maybe even until she's 6!" Milano told ET. Adding, "Everyone's fine with her nipples being out. I think people are more comfortable sexualizing breasts than relating them to what they were made for, which is feeding another human."

The actress - who is also mom to four-year-old son Milo with husband Dave Bugliari - also opened up about the joys of motherhood, telling ET, "When you have these babies, that connection is so meant to be and so profound. You look at them and you go, 'Oh, this is why. This is why I went through everything in my life.'"

Milano frequently post photos of herself breastfeeding her children. In November, the actress shared a photo, of herself breastfeeding her little girl while at work and in December posted a similar breastfeeding photo.

In April, the "Who's The Boss" alum spoke out after her breast milk was confiscated at Heathrow Airport in London, England. At the time, Milano told Us Weekly that breastfeeding her children was "one of the greatest joys."

"I don't want to turn this into a bigger issue than it is but I will say this ... breastfeeding my children has been one of the greatest joys of my life," she said at the time. "Every ounce of milk I'm able to produce for my child is nothing short of a miracle and to watch that milk be thrown away without any regard for my baby, was heartbreaking. It's not the fault of the security in the airport; they're following orders to keep us all safe. But I do I feel it is a policy that needs thoughtful reconsideration. I'm glad this has started a dialogue. My only hope is to make things easier for moms, breastfeeding and formula feeding moms, everywhere."