Medical Bills Son Has Lymphangioma

My son Riley was born in 2007 with a rare condition (1 in 10,000 births) called Lymphangioma.  He was born with a tumor under his tongue which caused the size of his tongue to extend out of his mouth for much of his infancy.  He has had 6 surgeries so far.  We have paid over $25,000 out of pocket (even with insurance).  We still owe several thousand for the last surgery and are in need of going through yet another surgery.  Riley is now 6 years old and though he is able to close his mouth and can speak fairly clear, his tongue is quite thick and has many lesions (look much like blisters) that cause other children to comment.  Luckily in first grade children are not overly judgemental and Riley's self esteem is in tact.  As he gets older, my hope for him would be that the size of his tongue can be reduced to close to normal size and that the lesions can finally be removed.

 Any help would be greatly appreciated, as we are struggling to make ends meet and cannot embark upon another surgery until the last one is paid off.  Thank you from the bottom of my heart!