Adding add'l support for beam
We're replacing the ceiling and walls in our kitchen. While we've got the walls and ceiling open we've noticed that the header that was added some time ago* to support part of the second floor is supported by a pair of 2x4 on one end. There's an opening in the floor that seems to be where a 4x4 would fit, but there's no 4x4 there. This has supported the 2nd floor and roof load for 25+ years, but since it's open we don't see the harm in adding some "help." Pix will follow this evening.
First, is there any harm in adding help? IOW, can I cause a problem by adding another support?
Second, should I add a 4x4, or a lally column? And do I just size the height and force it in there with a hammer like a well fitted wall stud? Or use a screw lally and adjust the height once it's in there.
Third, should I nail/lag this new member to the old 2x4s? I'm reluctant to touch them as their bearing the weight now.
* = Before we bought, and we bought in 95. Likely when the back extension was added, near as we can tell early 80s.