Dependent and Child dependent ILR

Hi,
Can any one help me on the topics below.

I am in tier 2 visa and my visa will be end in September 2020. I am already eligible for my ILR application as I have completed my Five years I am planning to apply in December. My questions is dose my wife and son needs to apply for extension with me or they can apply for extension in September 2020.

My second question is my wife get her tier 2 pbs dependent visa on November 2014 but she came to the UK in March 2016 can anyone advise me when she will be eligible for ILR application in November 2019 or March 2020.

My third question is does my son needs to be apply for ILR he born in outside UK or I can apply directly apply for settlements. I have spoke with one solicitor and he advised me my son doesn’t need for ILR application. I am bit confused if he is correct or not.

Thanks in advance for helping me

Regards

1. They can apply for an extension in September.

2. As she came to the UK so late after getting her visa, likely only 2021 for ilr.

3. Your son needs ilr and can apply when your wife does. Presumably you are asking if you can skip ilr and apply for citizenship directly, which he can't as he was born abroad.

Thank you for your advise.

Just one more added help requested I got my Tier 2 visa on September 2014 then change employer on April 2016. Do I need any letter from my previous employer? Also if I am not wrong change of sponsorship does not have any impact on my ILR.

Again thanks in advance for advise on this matter