Dark book. Hero's niece is kidnapped along with heroine

[ALEXIS]

Romance book with some dark themes.

Read it around last yearish

Two or three books in series, no standalones, I believe the description below if from book two or three in series.

Heroine is out shopping with hero's niece when heroine is injected with something and passes out but niece thinks she is unwell due to her diabetes and goes along with the kidnappers.

Kidnappers are heroine's step bro and chick who likes the hero.

Step bro later SA the heroine but threatened to bring down the niece if she didn't cooperate.

Chick who likes hero feels guilty and brings the niece to hero who was looking for them.

Hero finds heroine bleeding a lot and with a gun to the step bro and she passes out later.

She has surgery due to injuries and they find out she had a miscarriage.