An outraged Allison Kerr said she has "nothing to do with him anymore" after Lisa Miller, 18, proposed to dad Jim Kerr while visiting the Scottish International Airshow in Ayr last Friday.
Mr Kerr was the caretaker at Ms Miller's old school, Woodfarm High in East Renfrewshire.
Ms Kerr said:
"It's my dad and I'm 32 so imagine how me and my family feel seeing that? We have nothing to do with him anymore."