Help with Hierarchical Structure in Excel

Hey guys, I have been working on a project in Excel for weeks with no luck.

What I am trying to make is an interactive BoM (bill of materials) setup almost like a Family Tree with buttons to add new child items. I've been working on coding this for weeks with no luck. Here is a link to my youtube video that visually explains exactly what I am looking for.

I guess the main question is, what is the best way through VB to set up a hierarchical structure like that in the video?

Requirements are:
- Staying away from SmartArt
- Need buttons to add items and child items
- Must be able to add a new child anywhere without messing up the alignment of other rows
- All items must be separated by 1 space.
- Parent items must always re-size to contain all its child items, with a step of 1 cell for both top and bottom
- New Items are always 5 cells long

Problems I have had with my VB

- Because my buttons have macros referencing specific ranges of cells telling where to place the next child item, they get misaligned whenever item boxes are resized and added.

I think this will turn into a useful BoM tool for anyone to use, so the more people to help with this the better!

Thanks again!