Reality star Kailyn Lowry, 29, has posted a sweet family photo in celebration of the start of the school year! The Teen Mom 2 cast member, who is a proud mom to four boys, revealed her eldest son Isaac, 11, whom she shares with ex Jo Rivera, and son Lincoln, 7, whom she shares with ex-husband Javi Marroquin, 28, are going into the 6th and 2nd grades respectively.