About 7 years ago my parents gifted my sibling £30k as they needed it to purchase a house. A letter was drawn up by my parents and signed by my sibling to make it clear that I should be gifted an equal amount on the event of my parents death, linked to RPI. My parents have recently offered to gift me the same amount of money now, instead of me receiving money from the estate as planned. They have always been very clear that things should be equal between my sibling and I, hence the letter being written. Should this amount take into consideration RPI, or be the same amount as gifted 7 years ago?