One wrote, "That's so beautiful. Seeing my kids together interacting almost made me consider a third. Almost," and another commented, "A bundle of joy right there in one photo."
"Absolutely Gorgeous, an so precious. so much love in these photos. So beautiful to see," wrote a follower.
On Sam's Instagram, he posted a picture of his step-daughter Eve cuddling with Harper in bed.
He captioned the tender moment, "Big sister" with a purple heart.
After giving birth to Harper earlier this month, the family were thrilled on Saturday when they could take her home from the NICU.
They shared the highly anticipated news on Instagram by sharing a picture of the bub in Snez's arms with Sam smiling behind her at the hospital.
"Hometime Harper. 24 days and it's finally time to come home," wrote Sam.
During her hospital stay, Snez had expressed she was sad her daughters hadn't been able to meet their baby sister.
"I know she'll be home soon enough, and her three big sisters will finally be able to meet her but till then it's back and forth to the hospital a number of times a day whilst trying to keep it together," she shared.
Sam announced Harper's birth on Mother's day, telling fans that Snezana became "really sick" during labour.
"Before we knew it Harper was off to the special care unit, and Mum was into ICU," he explained at the time.
He continued on to gush over Snez's strength when Harper was taken away for treatment, saying: "Of course in true Snez Mum fashion her only thoughts were for her little baby, and it was breaking her heart that she couldn't hold her."
This story originally appeared on our sister site, Now To Love.