This is "The Palm of a Tiny Hand" (Romaji: Chiisana Te no Hira, Japanese: 小さな手のひら) from Clannad Original Soundtrack, with lyrics (Romaji, Kanji+Furigana, English and Vietnamese).
After 9 months of waiting, Ushio is finally coming. Tomoya and Nagisa will finally have a family. But this family will only count 2 members for the time being...
