companion robot
n. A robot designed to help and interact with a human being.
Examples
2004
Companies and consumers alike are showing strong interest in partner robots, according to the second survey on the topic by Nihon Keizai Shimbun Inc.

Partner robots — also known as companion robots — are defined as those that "live" with people in their homes, such as Sony Corp.'s Aibo. Industrial and other commercial-use robots are excluded.
—“People see partner robots making daily life easier,” The Nikkei Weekly, February 02, 2004
2002
It's the kind of research that could push us towards Sony's dream of a companion robot in most homes, expressed almost two years ago by Toshitada Doi, president of Sony Digital Creatures Laboratory.

"10 years from now, I believe most households will keep two or three personal robots and their performance will increase 100 times," Toshitada said. "My expectation is that these robots will be able to talk naturally with humans, say about the latest gossip."…

With the companion robots of the future already being developed, it's becoming apparent that many of them are being designed to look, and behave, just like us.
—Sean Nicholls, “faux friends,” Sydney Morning Herald, May 02, 2002
1984 (earliest)
This is the second important development involving Nicoa's Torrance-based subsidiary. Last month, Nicoa reported that Synergy Accounting was entering the personal robotics field and would be building and marketing its "Companion" robots by the second quarter of 1985.
—“Nicoa Corp. announced today…,” PR Newswire, July 10, 1984