How much is a RT ticket to San Diego?

I dropped Olivia off on Thursday for a long weekend in San Diego with her grandparents. Spencer drove down the coast and had planned catch up with them on Friday, but got delayed and met up with them this morning. When I asked Spencer how Olivia was doing, he said "I think she's mad at me, she hasn't said a word since I've arrived." Which made me very sad. It was sad enough that she whimpered when I put her into the back seat of the car with grandma and grandpa, it was even sadder to see her wave goodbye from the back seat with a sad look in her face. Thinking that the normally talkative and social Olivia is speechless breaks my heart.