Diesel likes Tennis Balls and not the cheap one that you can get for $1.00 for like 12 of them. She ripes them apart in about 2 seconds. She has a fancy for the expensive Wilson official tennis balls. She will sit for hours and hours and chew or suck on them. I like to think she is soothing herself. She make funny sounds and will put herself to sleep. I should have taken a video but the Hubs thought I was stupid and would embarrass her. I'll get it next time the hubs is out in his garage.