Rambunctious two year old while pregnant

Ok any mommas who have multiple littles I need your help/advise I’m currently 8 weeks with baby #2 and my son is a crazy 2 year old. He’s not bad or mean he’s just a boy who loves to play roughly. For the most part he understands that he has to be soft and nice to mommy’s belly/the baby but like any toddler he’ll forget or have a tantrum and kick or want to play so he’ll jump on my belly. I’m terrified of him hurting the baby or making me miscarry. What can I do to protect my second baby from getting hurt?