This text makes it completely clear that Kiki loves her children completely and unquestionably. Even when they do things to exasperate her or when they do things that are illegal, as she suspects Levi of doing, she continues to love them with a love that is unshakeable, in spite of her anger and what a dominant and fierce individual she can be. This love becomes even more important due to her estranged marriage with Howard after she discovers the identity of his one-time mistress. Note the following quote, that describes how Kiki sees her children after the funeral of Carlene Kipps:
Kiki heard her children's clattering footsteps reverberate through the archways behind her. They rushed towards her like the shadows of people escaped from their graves, and came to a halt by her feet, panting and laughing. She could no longer see their features in this dusk, only the outlines and movements of beloved faces she knew by heart.
The reference to the way she knows their faces and appearances "by heart," even though she can't actually see their features any more in the dusk clearly points towards an incredibly strong mother-child bond that she has with each of her children. Kiki is a mother who is always there for her children and does her best to support them in life with the kind of patient and, at times, tough love that only a mother can display.