Umbilical hernia

My baby has an umbilical hernia, she was diagnosed by a doctor, they told me to leave it alone but my Mexican family are telling me to use the coin trick to make it an innie, the hernia does goes down when I push it gently in and it stays in but when she grunts or cry or poop it pops back up, is there a chance it will close up? Never had this with my other kids