"Sister's Preventable Illness Trifecta Spoils Holiday Festivities"

A reader is frustrated with their sister for repeatedly attending family gatherings while sick, leading to the reader catching a cold and missing out on time with their grandkids. The advice given suggests empathizing with the sister's loneliness, offering alternative solutions like wearing masks, and finding ways to manage one's own anger. Another reader struggles with the lack of relationship with their father and half-brother, and is advised to focus on the relationships they do have. Lastly, a co-parenting reader seeks advice on handling sibling arguments, with the suggestion to establish clear rules and consequences in their own home and to encourage the children to resolve disputes themselves.