Hi Notsoy,
I agree with Eugenes opinion about your inlaws: they should mind their own business. But that is one of the joys of familiy 
However, for me the signs that Eugenes has mentioned are more of someone already half trained more than someone who has not even began! I would step back a bit first.
For example, I started with mine by putting the potty next to the toilet and then we would both play the "wee wee game": I would do it for real and then I would encourage her to imitate me. I did not ask her to put down her trousers yet, just to sit on the potty and the to "clean" her bottom and wash her hands. I would also play the "wee wee game" with a doll or a teddy.
After she had managed the ritual a few times in 2 or 3 weeks (no pressure), I chose a time of the day when we would try to do it for real. For me it was at the time of the night bath. I took away her clothes and ask her to sit in the potty and do a real wee-wee while I was preparing the bath. I would insist that she stayed seated for a little while (unless she got upset) and sometimes I would wet her hands and legs a bit to try to provoke a pee response. Finally I got her to pee in the potty and I made a big fuss of it.
I continued the routine every night for another few weeks until she was doing a wee almost every evening. Then I took the plunge and used a long weekend to do a full potty training: Nappies completely off except for the night, bare bottoms and potty in the middle of the room and asking her to use it. Stickers, candy and other rewards if success (e.g. I let her play with my iPhone if she did it right), calmly leaning the messes when she failed. We are on day 5 and she only had 2 accidents and all the poos in!
The good thing about all the preparation and games that I did before is that I could assess by myself if she was ready or not. If she had gotten too upset about the potty and never managed to pee regularly for a few evenings, I would have waited. I think that this was better than following some list of "readiness" signs. There are too many "magic" lists out there and they all tell you different stuff, some of it quite absurd and impossible to check.
my2cents