The 20-year-old's character Lola Pearce is currently involved in a custody battle with social workers over the care of her baby daughter Lexi.
The plot has met with a negative reaction from social workers due to the handling of lead investigator Trish Barnes (Tessa Churchard).
Harold explained that she made sure to do plenty of research before starting the storyline and that she has had "fun" filming it.
"When I first started I did a lot of research into care and people who'd been in care," she told The Sun. "I wanted to see how people felt about it because I couldn't imagine growing up without my family.
"When it came to Lola's baby getting taken away I could easily imagine how horrible that is. It's the same sort of pain as someone dying. The worst pain you could possibly feel as a young girl would be having your baby taken away. So I just let it play out and the emotions came.
"It is my dream storyline, it's got so many different levels. There are happy bits, sad bits, angry bits, it's got everything you want. It's a great storyline to play and fun to act out."
Harold revealed that filming so many scenes with a baby has made her broody in real life.
"I found it really difficult. I've never had a baby so I couldn't imagine what that pain would feel like," she said. "I just kept thinking it would be the worst pain imaginable.
"I love playing a mum now and working with the two babies who play Lexi, they are so cute.
"Playing someone who was pregnant did make me a bit broody. I found myself walking around the canteen rubbing my bump. Then I'd get on the train and think, 'Aren't you gonna let a pregnant woman sit down?' because I'd forget I wasn't really pregnant.
"But I don't think I'm ready for one yet. It's nice to give the baby back when she cries."
The actress added that she has found it awkward kissing co-star Jamie Borthwick, who plays Jay in the soap.
"Jamie's lovely. We're like brother and sister," she said. "We have loads of banter and loads of fun. With kissing scenes we just have to laugh about it.
"No, I'm not going to say if he's a good kisser! Write this, 'He is a very good kisser... jokin!' I could never see Jamie like that, ever. He's like a little brother and we just have a laugh."
EastEnders continues on Monday, October 29 at 8pm on BBC One.