ILR Eligibility for a 4 year child via skilled worker/Tier 2 dependant route

Hello admins,

I will really appreciate if someone can help me on the following issue.

I migrated to the UK in 2010, and after completing my 5 year Tier 2 (general) route, got my UK nationality in 2020.
I got married in 2018 and brought my wife to UK on Tier 2 dependent visa in June 2018.
My son was born in March 2019 outside UK and we brought him to UK on Tier 2 dependent visa as well in May 2019.
My wife has now completed her 5 years this month and is now eligible for ILR through Tier 2/Skilled worker dependent visa.
However I am unsure about whether my son, who is 4 year and 3 months old and has not completed his 5 years technically, is eligible to apply for ILR now, or he has to wait for another 9 months before he completes his 5 years.
My understanding after reading the eligibility criteria is that my son doesnt need to complete 5 years and can apply with my wife.

Please can anyone reply to this?
Thanks a lot and much appreciated.

He can apply for ILR when your spouse does. There is no minimum 5 years for children. They qualify for ILR when both parents do or when the one has ILR and the other is applying.

Thank you so much sir for the reply. Highly appreciated.