"A man never stands so tall as when he leans over to help a child." Who said this quote and what does it mean to all of humanity?

"A man never stands so tall as when he leans over to help a child." - Abraham Lincoln

https://handshakefoundation.org/about-us/

Seems like it is being applied to rights of children in custody cases. It can also be taken in many ways, looking out for a child's welfare and the shaping of a child's future. The UN Convention on the Rights of the Child states that a child "should grow up in a family environment, in an atmosphere of happiness, love, and understanding" and that "parties shall respect the right of the child who is separated from one or both parents to maintain personal relations and direct contact with both parents on a regular basis." Too often this as not a reality for children of separation and divorce. It must become a reality.