MeleahR's list "Gemma's Future Sibling" of 4 great name ideas: Thomas - Eva!

Gemma's Future Sibling

A solid classic with plenty of history, Thomas strikes the balance between strength and gentleness. A favorite in the UK, a staple in France, and Australia, and never absent from the US Top 100, Thomas feels like a safe bet and a name that fits into any era. 
The Greek form of the Aramaic name Ta’oma, Thomas means "twin." It came about in the Bible because there were too many apostles called Judas, and so, Thomas became the "twin", to reflect his close brotherhood with Jesus. 
Known as "Doubting Thomas" due to his initial skepticism of Jesus’s resurrection, he went on to become a martyr, and there was no need to doubt Thomas’s potential as a given name. 
Brought into common usage by the Normans, it was then always among the 5 most common English names for boys at any point between the 13th and 19th century. 
While it has fallen down the US charts in recent years, it remains a familiar and trusted choice. Given to over 6000 boys every year, it has made a steady climb back into the Top 50. 
Across the pond in the UK, both Thomas and Tommy make the Top 30, while Tom, Tommy-Lee and Tommie have made their mark in the Top 1000. 
As a well-established classic, Thomas naturally comes with plenty of noteworthy namesakes. "Thomas the Tank Engine" might appeal to you kids, but there’s also the theologian, Sir Thomas Aquinas, the cardinal Thomas Wolsey, the Founding Father, Thomas Jefferson. the philosopher, Thomas Hobbes, and the writer, Thomas Hardy. 
More recent namesakes for those who aren’t into history include actors Tom Hardy, Tom Cruise, and Tom Hiddleston, singers Tom Parker and Tom Fletcher, Olympic diver Tom Daley, and Thomas Sanders, of YouTube fame. 
A timeless all-rounder, Thomas comes with the intuitive nicknames, Tommy and Tom, which feel sweet for a child but not too cutesy for a grown-up. For more unexpected options, you could try the nature-inspired Moss or Scottish Tam. 
Unlikely to go out of style anytime soon, Thomas is a refined but approachable choice. If the popularity does give you pause, however, you could try the surname-inspired Thompson, or an <a href="https://nameberry.com/list/492/100-classic-boys-names--below-the-top-1000/all"> underused classic</a> like Marius, Rufus, or Phinneas. 
Alternatively, there is a wealth of interesting variants to ponder, from Italian Tommaso and Scottish Tavish to Croatian Tomo– and for girls, there’s Thomasina, Tomine and Tamsin.

Thomas

Isaac has shaved off his biblical beard and leaped into the upper echelon of popular boys' names, outrunning cousin Isaiah. A favorite of the Puritans, Isaac has never dipped below Number 400 on the US list of top boy names.
 Isaac evolved from the name Yitzchaq, derived from the Hebrew word tzachaq, meaning "to laugh." In the Old Testament, Isaac was the long-awaited son of the elderly Sarah and 100-year-old Abraham, so old that their news provoked laughter, giving the name its meaning. Isaac is used as a given name among Jews, Christians, and Muslims alike.
 
A baby given this name can point to many distinguished namesakes, including Isaacs (and Izaaks) Newton, Walton, Bashevis Singer, Asimov, Stern, Hayes, and Hanson.
 
Isaac also boasts the cute nicknames of Izzy — now shared, however, with a bevy of Isabellas — and Ike.

Isaac

Hadley, most famous as the name of Ernest Hemingway's first wife, is more sophisticated, professional, and modern than cousins Harley, Haley, or Hayden. 

The hit book The Paris Wife, a novel by Paula McLain told from the point of view of Hadley Hemingway (born Elizabeth Hadley Richardson), has helped popularize the name, which also appears on the vampire show True Blood. Hadley could become this generation's Hailey.

Adley, a mashup of Hadley and Addie, has also appeared on the scene.

Hadley

Eva is a simple, classic <a href="https://nameberry.com/baby-names/489/hebrew-names-for-girls">Hebrew name for girls</a> that recently slipped out of the US Top 100 for the first time in more than a decade. Pronounced either like her more popular sister Ava or less popular sister Eve, Eva is one of the elite group of <a href="https://nameberry.com/list/607/girls-names-that-mean-life">girl names that mean life</a>.
 
Eva is found in many different languages as a variation of Eve—the Old Testament name recognizable as the first woman in Abrahamic religions. Short forms of the name include Evie and Evita. The diminutive Evita is still strongly associated with Evita Peron, wife of the Argentine President Juan Peron.
 The 1852 publication of Uncle Tom's Cabin, the bestselling novel of the nineteenth century, whose tragic figure Little Eva (short for Evangeline) made an enormous impression on the Victorian reading public, propelled the name to popularity.
 Some well known Evas include actresses Evas Marie Saint, Gabor, Green, Longoria and Mendes, sculptor Eva Hesse, singer Little Eva, and model Eva Herzigova
 Eva is a highly popular <a href="https://nameberry.com/girls-names">girls’ name</a> throughout the Western World, ranking in the Top 100 of most English-speaking countries along with a wide range of European nations, from Spain and Italy to France and Germany to Scandinavia. This makes Eva one of the most internationally versatile names today.

Gemma's Future Sibling

The names

Thomas

Isaac

Hadley

Eva