You had chosen the twins' names from the names of Loki's and Sigyn's twins in Norse mythology. Those twins had both been male, but you'd agreed it was safe to use the names regardless of gender. With the twins being half-Jotun, they were likely gender fluid like their father. All Jotuns were gender fluid after all.
The other concern had been that the names were cursed, given the fate of the twins in mythology. You'd decided that since you and Loki weren't following your fates from the myths, that your children wouldn't follow their mythological counterparts' either. Some might think that you were tempting fate, but you had hope that they were wrong.
And so Loki let you get away with your homage to the myths.
As with most husbands across the nine realms, Loki had simply gone "Yes, dear" to the requests of his pregnant wife. Especially when you'd made this decision while you were as huge as a house with twins who were far too big for you. You had the feeling that Loki actually liked the names, though he didn't admit it. Loki was a little shit who enjoying thumbing his nose at the myths. Especially since most of the myths were made up by Thor and his idiot friends when they were drunk on Midgard and hanging out with the Vikings.
Now that their names had been chosen, you could look over them more properly. It was no question that you would never have been able to have delivered the twins naturally. You knew you'd been as big as a house. You knew the children were half-Jotun. You still didn't expect them to not look at all like infants, but instead they resembled six month olds. Or possibly older. Children's ages weren't your strong suit. They could already hold their heads up, and looked like it was a matter of days before they figured out how to toddle around.
Your son had raven black hair already and his father's green eyes. They were filled with just as much mischief as Loki's, but also the love for you that you always saw in Loki's eyes. He was a mama's boy already. He squalled when you tried to pass him to Loki and clutched onto a lock of your hair so you couldn't dislodge him. You chuckled at his antics and cuddled him close as he wanted.
Your daughter on the other hand, was absolutely a daddy's girl. She sat on Loki's lap and the pair of them played with magic together. Loki created little streamers and balls of light and Vali copied him. Her grasp on magic at such a young age was remarkable.
You all sat together on the bed for awhile, getting to know each other and speaking telepathically with your children. They were absolutely perfect.
You wanted to kick Loki out of the room when it was time to try to nurse the twins. You were embarrassed and sure you were going to do it wrong. Or worse, that you wouldn't be able to. You had no way of knowing if you could produce enough milk for half-giant twins. Loki, of course, protested leaving his children. It took some trying, but you managed to feed both of your twins, though you and Frigga both noted that you wouldn't be able to keep it up. Luckily, you had the means to get formula. It was only a temporary solution, but only had to be. They would grow fast enough that they wouldn't need milk to survive as they would be able to move on to real food.
You settled back among the pillows, cuddling your son in your lap when they'd eaten and let Loki have his daughter back. She was perfectly happy with her beloved papa. You stroked Narvi's hair and cuddled your shy son to you every time a new healer came to check on you. He was quite like his father and didn't like strangers it seemed.
Frigga noticed that he was small, like Loki had been, and the giants would consider them both runts. Though Vali seemed more lively and healthy than her brother. It had you and Frigga both concerned, but you saw the glint in her eyes that she knew you would both be keeping eyes on your son to make sure he stayed ok.
Once you were settled and comfortable, cuddled up with Loki with Narvi in your arms and Vali in his, the twins dozing peacefully, Frigga looked to you. "So, darling, would you like to tell me how you've become a valkyrie?" She asked calmly.
You sighed and figured you were going to be tired of telling this story very quickly. You started at the beginning and told her everything that had happened. Frigga sat quietly and listened, though you saw the spark of pain in her eyes at the mention of her daughter. You tried to reassure her that Hela was well on Helheim and ruling it and her valkyrie.
"I'm glad you're back among the living, darling. And glad that the valkyrie will be returning to us. Their presence on Asgard has been sorely missed," Frigga finally said. She was still shocked, you could see it in her eyes. Everyone would be shocked. Hel, you were shocked, but she had centuries of ruling behind her to keep her emotions from her face, from holding her back from doing the things that needed doing.
You spent a week in the healing wing with the twins. Loki was there every spare moment he could get away from his duties. It was tradition that you got time to recover from the birth, even moreso since you'd died in the process. There were also spells to return you to your pre-pregnancy size and body in the week. Magic was amazing sometimes.
No one except family was allowed to disturb you while you recovered and while you bonded with your children. All too soon, though, the week of magical healing ended and you would have to go back to your duties on the realm.
