Kyle's celebrity pals were quick to gush over his baby boy, with Dannii Minogue commenting, "Cutest photo. Congratulations," while singer Kate Ceberano also sent her well wishes to the radio host.
The second snap, taken by midwife Vicki Rushton, shows Kyle in awe of baby Otto as he holds the swaddled bub shortly after his birth.
The 51-year-old also revealed that he and Tegan have been in a "love bubble" since the birth of their first child.
“We just keep looking at him, and then we look at each other and smile and one of us has a little tear roll down,” he admitted.
The sweet snaps come following Kyle sharing a video of Otto on The Kyle and Jackie O Show last week.
"Here he is!" he announced in the clip, panning the camera across to his son who was wrapped in a colourful blanket.
"Oh he's so cute! Look at him," Jackie exclaimed from the radio studio.
"I do think it does look like you Kyle."
She then asked what colour Otto's hair was.
"I thought it was like a strawberry, brown-y, goopy bit of whatever in there," he said.
Someone else chimed in that they saw the resemblance in Otto's "round face", to which an affronted Kyle replied, "Excuse me!".
He also shared some more details following his son's birth, saying, "Otto is born, Otto is fabulous, I cut the cord, I didn't realise it was like tough calamari, and blood squirted out."
He added that Tegan had remained in hospital after the delivery, but all was well with mum and bub.
“The baby is all clear but because Tegan had a caesarean she’s just got to keep that monitored, but she’s doing well,” he said.