If you allow him to remain on the team then you are sending the wrong message. Every rep he gets in practice is a rep someone else needs to get. He has cut himself and he needs to know it , his parents need to know it , and everyone who ever thinks about being a part of your program needs to know it.
How many kids miss church service on Weds nights to practice or play games? How many kids miss important family functions on the weekends? How many kids really could stand to work a part time job but the family does without so the kid can play? The fact is you have to sacrifice to be a part of a team. Everyone does.
If you allow this player to miss and remain on the team how long before someone else comes up with a reason to miss? "Well coach you allowed Jimmy to miss!" No imo this is cut and dry period. Its not open for debate or discussion or meetings. Cut him and move on.