He who is not Merciful to People
Jarir bin Abdullah (radi Allahu anhu) reported that the Messenger of Allah (sal Allahu alaihi wa sallam) said, “He who is not merciful to people Allah will not be merciful to him.”
[Sahih al-Bukhari and Muslim]
Kind treatment to Allah’s creatures is very much liked by Allah. Even animals and birds are included in this category. Kind treatment with them makes a person eligible to the Mercy of Allah.
Decent behavior with people has been specifically mentioned in this Hadith although all creatures are covered by it.
And Allah Knows Best!