Be close to their heart - Idioms by The Free Dictionary
be close to (one's) heart (redirected from be close to their heart)
be close to (one's) heart
To be personally important to, or loved by, one. The little girl who came to visit the elderly woman every weekend was very close to her heart.
be close/dear/near to somebody’s ˈheart be a person or thing that somebody is very fond of, concerned about, interested in, etc: The campaign to keep our local hospital open is something that is very close to my heart.