Julia's father is being referred to respectfully, hence why we use रहे and हैं (with the anuswar).

See the "Formality and Respect" section in the Family Tips and Notes:

In formal situations and for respected people (including all elders), plural versions are used in every context. For example, with पिता (father): मेरे पिता भारत में हैं - My father is in India; उसके पिता अमेरिका से नहीं हैं - His father is not from America.