"My baby first day of school! Where has the time gone? SO PROUD OF YOU BOOBOO," he captioned the snapshot.
Royalty's mom Nia Guzman shared the same image on her Instagram account. "Kindergarten here we come!!" she wrote on the photo.
Chris, 30, and Nia, 36, amicably coparent Royalty, 5. They previously fought over custody and child support payments but they have been on good terms in recent years.
The "No Guidance" crooner is reportedly expecting a son with ex Ammika Harris, but neither party has confirmed the news.
Ammika, 26, has kept fans guessing about her reported pregnancy by hiding any signs of a baby bump on her Instagram, but Chris has been putting out little clues.
Chris wrote "BM bad" on one of Ammika's photos in May 2019, which fans took to be an abbreviation for "baby mama."
Do you think Chris & Ammika will confirm their pregnancy news soon? Sound off in the comments below!