@Background Pony #E4DE  
I know, lets hope they go out with a bang.

2019!

@Chicago Ted  
Thanks, before I go to bed here are my picks for the cake twins when they are grown-up.
 
Pound Cake-Nolan North  
Pumpkin Cake-Hynden Walch

@David Dyster  

FTFY

Here are some of my voice ideas for the cake siblings when they are older.
 
Top 10 voices for older Pound Cake  
1)Freddie Prinze, Jr.-best known for Kanan Jarrus from Star Wars Rebles(2014-Present)  
2)Andrew Francis-best known for Shining Armor from My Little Pony: Friendship is Magic(2010-Present)  
3)Nic Rouleau-best known for Elder Kevin Price from The Book of Mormon (2011)  
4)Anton Yelchin [R.I.P]-best known for Ensign Pavel Chekov from J.J Abrum’s Star Trek trilogy(2009-2016)  
5)Mikey Kelley-best known for Alastor from Viewtiful Joe(2003)  
6)Jamie Bell-best known for Tintin from The Adventures of Tintin(2011)  
7)Johnny Yong Bosch-best known for Ichigo Kurosaki from Bleach(2004-2012)  
8)Dan Green-best known for Yugi Mutou/Yami Yugi/Pharaoh Atem from Yu-Gi-Oh!(JAPAN:2000-2004, USA:2001-2006)  
9)Nolan North-best known for Nathon Drake from Uncharted series(2007-2016)  
10)Tom Kenny-best known for SpongeBob from SpongeBob SquarePants(1999-Present)
 
Top 10 voices for older Pumpkin Cake  
1)Laura Bailey-best known for Lust from Fullmetal Alchemist(2003-2004)  
2)Cree Summer-best known for Susie Carmichael from Rugrats(1991-2004)  
3)Grey DeLisle-best known for Beatrice Bixby/Lady Redundant Woman, Ms. Question, Mrs. Ripley, additional voices from Wordgirl(2007-2015)  
4)Natalie Portman-best known for Nina Sayers from Black Swan(2010)  
5)Hynden Walch-best known for Starfire, Blackfire, Madame Rouge, Argent from Teen Titans(2003-2006)  
6)Evangeline Lilly-best known for Kate Austen from Lost(2004-2010)  
7)Amy Poehler-best known for Leslie Knope from Parks and Recreation(2009-2015)  
8)Ginnifer Goodwin-best known for Judy Hopps from Zootopia(2016)  
9)Nicole Oliver-best known for Zoe Trent from Littlest Pet Shop(2012-2016)  
10)Tiya Sircar-best known for Sabine Wren from Star Wars Rebels(2014-Present)
 
Let me known in the comments and I will catch you guys later. PEACE!

Not a bad conjecture, if you ask me.