Upvote:1
Can I (IT professional) support my wife ?
Yes, absolutely.
Can my father-in-law (retired) support my mother-in-law?
Yes!
There are several people on here who have had third parties provide the funding for their visas and have obtained the visas. The closest third party one could have is an immediate family member, typically a spouse.
The yeses are conditional on you/father having the income generating assets and/or jobs and pensions (in your fathers case) to support them and the trip. Note that bank statements are not only about sufficient funds, but the ACTIVITY in the statement. Don't get caught in funds parking issues and ensure that the provenance of the funds in your account are clear etc.