Niini no Koto wo Wasurenaide (2009)

Both protagonist suffer a rare chronic diseases that slowly weaken their bodies and made it hard for them to live their daily lives like other people. Both protagonists faces many hardships and struggles as they try to fight against their diseases with the support of their families. And both protagonists try their best to live until the very end.

Characters that want to live their life but have to overcome similar obstacles like facing death and accepting their life while thinking about the future.
-Have a similar feel (VERY similar)
-Disease causes struggle within the family
-Both end on a very sad but happy note

They are both specials of true stories about people getting diseases that can't easily be cured. Throughout both the characters remain optimistic and willful to live until the very end with the help of their family and friends along the way.