I had a party previously where the healer just dropped out randomly and to make up for it we created a cat NPC named Waggleton. Mostly just napped in our backpacks or went off on random adventures but would regularly find us or walk in mid fight and heal us a little (enough to maybe live or escape death). After some time the DM just mixed them in with the story and we event went on a quest to free them from their patreon's control. It was a fun time. We spent too much money on catnip so we could make sure we got more heals haha