Are we forced to meet our mother if we are not willing to ?

Hello , my mother had an affair 4 years back and she ran with all the savings we had for our future. She then filed a divorce case against my father saying that he consume alcohol and hit her also abuse her. Which are truly false allegation. My father is truly innocent and that's why we are with him. We are 4 siblings 22 , 17 , 13 and 9. I am 22 year old and I try to support my father with everything I can in court . My mother is a lier and she lies so perfectly in court with tears that it looks like she has faced alot. Although that is false. My mother use to be very violent to us at home . 1st she ran she left my 6yr old brother in school and she ran later she came back and packed her bag and went. That time my 13 yr old sister tried stopping her but she hit her really badly and she suffered so much that we had to consult her to a psychologist. Tooday my mother is asking for custody for my 9 yr old brother and he is not willing to meet her at all. She tried forcing him to meet him also tried to meet him secretly in school.. after seeing her he gets so scared that he suffers fever. We don't want to meet her at all. Court is forcing us to meet her. We feel depressed to meet her. What can we do. We want to move on with our life and stay peacefully with our dad. Please help us out. We truly need help. Please suggest me what can I do to protect my siblings from this as I am 22 what actions I can take. As I am the one who is looking after them for 4 years. Its very depressing for us. Help us and suggest us please