I was originally planning on writing one post about Freya’s Husband and one about Her Children but there is so little information about Them all that I might as well write one short post instead of two very short one.
Let’s start with the Husband, as He’s the one we know the most about.

What do we know about Freya’s Husband, Odr? Very little. The Eddas tell us His Name and that He is always away on long journeys. This makes Freya cry tears of gold of longing for Him and She often travels in disguise throughout the world in search of Him.
What is most interesting is that His Name, which can be translated as ‘frenzy’, ‘ecstasy’, ‘inspiration’ or ‘poetry’, is etymogycally very close to Odin, whose Name means ‘Lord of frenzy’. This has made many theorise that They are in fact the same Deity. Which could mean that He is either married to both Frigga and Freya or that Frigga and Freya are two aspects/Names of the same Goddess. Neither theory is particularly far-fetched considering that the Deities aren’t exactly known for Their monogamy and that They also tend to have many different Names and titles.
What about Freya’s Children? One of Them is a Goddess named Hnoss. In Gylfaginning 34-35, we are told that She is so beautiful that whatever is beautiful and precious is call hnossir, meaning treasures. The same passage also tells us Odr is Her Father.
A poem preserved in Skáldskaparmál (verses 36-37) makes me think there might be a connection between the tears of gold Freya cries for Her Beloved and the Goddess Hnoss:
I am able to possess Horn’s (Freya’s) gold-wrapped glorious child. We received a valuable treasure (hnoss = treasure) Ocean’s fire (gold) rests on shield’s damager. Freyr’s niece bears her mother’s eyelash-rain.

Freya has another Daughter called Gersimi, whose Name also means ‘treasure’. She is mentioned shortly alongside Her Sister in Skáldskaparmál and in Ynglinga Saga. Nothing else is told about Her. Because Her Name means the same as Hnoss, some have theorised that They are one and the same. This would also explain why only Hnoss is mentioned as Freya’s Daughter in other places.
As far as the surviving lore tells us, Freya has no Sons and no other Children .