My question involves child support in the State of: VA

I have received a summons from the Juvenile and Domestic Relations District Court. Summons states “increase Child Support as the Parties’ Incomes have increased. Father to pay ½ of all child’s summer camp/day care expenses. Father to pay for all travel expenses”.

Quick back story: Separated from ex. Myself and ex have split custody of our kids. She has physical custody of our daughter (4 years old) and I have physical custody of our son (14 years old). She resides in VA whereas I reside in Germany. I currently pay CS to her but she is requesting an increase in CS. My income has increased since I moved to Germany due to housing cost being paid for, Cost of Living adjustment, and education cost (Son school is paid for but is considered income). What are my rights and what are my options? Am I required to appear at summons? Can travel expenses be split between parties? Is Cost of living taken in consideration since Son lives in Germany?

Would getting a lawyer be the best way of handling this...