Question: Capital Gains with Land Sale

[Allison J.]

1. Hello! New here and very new to the real estate world and have a Capital gains question in regards to a land sale. (If this post belongs elsewhere please advise.)
2. My father recently purchased a single family home in MA in December 2020 as his primary residence. The property sits on a 5 acre lot and includes enough road frontage to parcel off some land for me to potentially purchase and build a home.
   
3. My question- is there any legal tax loophole to avoid my father having to pay short term capital gains if I purchase this land parcel from him before he has owned the property for 1 year?
4. How are short term and long term capital gains calculated when parcelling off part of your property to sell in MA?
5. I understand the capital gains is taxed on the “profit” of the sale. Not sure how the “original value” of a 1.5 acre parcel would be determined if the original purchase price included the entire 5 acres and a house?
6. Should I wait until Dec 2021 to do any “improvements” (i.e.) clearing/ leveling land and putting foundation in on the new 1 acre parcel? I assume any improvements will increase the value of the property and increase the value at time of purchase and consequently increase short term capital gain tax.
7. Thank you very much for any thoughts.