Maia Bouchier and Alice Davidson-Richards have been added to England's T20 squad in the West Indies following Alice Capsey's withdrawal from the tour.
Capsey broke her left collarbone during the first ODI in the Caribbean, ruling her out for the remainder of the trip.
England have coped comfortably in the teenage all-rounder's absence, taking an unassailable 2-0 lead in Antigua before Friday's series finale, but have strengthened their hand for the five T20s which follow.
Bouchier, who has 14 caps, will fly out to join the squad after being initially overlooked by selectors while Davidson-Richards stays on having originally been picked only for the 50-over leg.
England's initial outings under new head coach Jon Lewis have been highly encouraging, with seamer Lauren Bell starring in the second ODI with career-best figures of 4-33.
Reflecting on a second successive 142-run win, she said: "It was a great team performance. We're really proud of the way we played.
"Lewy [Lewis] has talked a lot about playing without fear and there being no limit on what we can achieve, I feel like we saw that today.
"Personally, I just stuck to my plan and to get a career best in a game that sealed the ODI series is really cool.
"We're not particularly looking at changing our game plan as we continue the rest of the tour, our minds are on each game as they come and playing with the same aggression and positivity we did today, it's very freeing."
England's white-ball tour of the Caribbean continues with the third ODI taking place on Friday ahead of five T20 internationals.
England women in West Indies
Friday, December 9: Third ODI, Antigua (6pm UK time)
Sunday, December 11: First IT20, Antigua (10pm UK time)
Wednesday, December 14: Second IT20, Barbados (10pm UK time)
Saturday, December 17: Third IT20, Barbados (10pm UK time)
Sunday, December 18: Fourth IT20, Barbados (10pm UK time)
Thursday, December 22: Fifth IT20, Barbados (10pm UK time)