Practicing sitting

Jackson is 5 months old now and growing so fast! He is rolling over from his back to his tummy like a champ, though he needs to work on rolling from tummy to back. He is waking up alot at night, stranded on his tummy, confused as to how he ended up that way and how to fix it. He now sleeps with wedges to keep him from rolling. He is also working on sitting up. He much prefers standing.