Here's how Snowdrop receive her letter in The Snowdrop Movie.
[We see Snowdrop lying in bed softly snoring. When Primrose appears]
Primrose: Wake up, my filly.
Snowdrop: [wakes up] Mother?
Snowdorp: Good morning.
Primrose: You 2. [nuzzles her]
Snowdrop: [giggles] [then something hits the back of her head] Ow! [uses her force vision] What's this?
[it was an envelope!]
Snowdrop: An evelope?
[Eaglesight then his claws to open it for her]
Snowdrop: What does it say, Mother?
Primrose: [reading] It's letter from our other relatives!
Snowdrop: [gasps] What's it say?!
Primrose: "Dear Snowdrop, this is your friends, we hope you sleep well, eat better, stay warm, keep high hopes, love, your family".
Snowdrop: [jumping up and down] I got a letter from our relatives!
Snowdrop: I GOT A LETTER FROM MY RELATIVES!! [laughs crazy]
[she then race through the town calling out about her letter and soon many of the others start to wake up and hear her]
Skyla: [gasps] It worked!
Astrid: [groaning] What's gotten Snowy so excited now? Come on, Stormfly.
[she and Stormfly, soon followed by the others head for her]
Yuna: Snowdrop, what's got you so excited?
Snowdrop: I got a letter from my relatives, duh!
Hiccup: No way!
Snowdrop: Yes! You know they could be coming tonight!
[Sound of glass breaking. Skyla's pupils shrink to dots]
Armor Bride: Uh, tonight?
Sweetie Heart: Huh?
Britney Sweet: Wha?
Scander: Uh oh.
[Later Snowdrop and the dragons are setting up preperations]
Skyla: [comes up] Snowdrop, what are you doing?
Snowdorp: Making preperations!
Skyla: Oh, okay.
Snowdrop: Yeah! [hugs her]
Skyla: [heart sank] Uh, Snowdrop, about that...
Snowdrop: Not now. I've got to get finished!
[No matter how hard the foals tried, they didn't had to heart to tell Snowdrop the truth]
Button Mash: This is bad.
Sweetie Belle: Very bad!
Scander: [sarcastically] So, do you have any more bright ideas, Sky?
Skyla: I got it!