christopher swist was on a break from a relationship with jessica mccarty when she allegedly killed her children in palm bay , florida , police say .
lacey mccarty , seven , phillip mccarty , six , and swist 's son with mccarty , a five-month-old also named christopher swist , died in march .
swist was close with the kids and coached the two oldest in little league .
he 's created a non-profit for underprivileged kids in honor of the children .
a little league baseball field in palm bay has been renamed ` angels ' field ' as a memorial for the slain kids .
mccarty faces three counts of first-degree murder for the incident .