The first one worked in Singapore and she couldn't speak much Cantonese and learned slowly in Cantonese. She rarely spoke to me. The second one worked in Taiwan and speaks good Mandarin. She learns Cantonese faster than the first one and likes speaking a lot in front of me.
I think it all depends on the person, her personality and her speaking skills. Surely I talk to her when I feel comfortable, asking her whatever about my BB. Ask her to report once what she did in the daytime. WHat she did on her holidays... Talk about her friends in hong kong... etc. ASk her what she can do for BB, like making suggestions on congee, etc.