Grounds will remain same to see my father as my mom is also in 75+.As your parents have already been in Canada since the last 14 years (roughly around the time your daughter was born), they had the opportunity to meet your daughter in India.... at the time of her birth and/or her first birthday (just some reasons to meet her).
Also, your daughter could have applied in the last 14 years to see her grandparents.
My parents were traveling to India past 12 years but since last year due to health reasons they didn't get access to travel .secondly if I travel again it's not possible for me to leave my child alone in india
You can travel to/attempt to enter Canada as many times as you like until the validity of your multiple entry TRV. Do be aware that at some point the immigration officer may restrict/limit the duration of your stay or even deny entry if s/he believes you are violating visitor visa privilieges.
I am law abiding citizen and never try to violate laws n limitations.
Your visitor status can be extended. But what grounds would you seek an extension considering you have other family members who can take care of your dad?
Otherwise you need to apply for a new TRV from scratch when your current TRV expires + when you're outside Canada
My stay here was great emotional support to my parents.i accompanied my father's to all the dctr appointments..right from beginning we been very transparent with the system and provided all details true to the fact